Aegist
So it says about 10,300 active plugin users.
A more appropriate plugin for the OP's question is Hypothes.is. They're open source, non-profit and have raised over $1.5 million. They have about 7,300 users according to the chrome webstore: https://chrome.google.com/webstore/detail/hypothesis-web-pdf...
However rbutr isn't really what you've described here. What you've described is either
Oh, also, Hypothes.is had previously put together this spreadsheet on Google Docs which lists all of the previous efforts to make web annotation applications. It hasn't been kept up to date though so I keep a local one up to date now, just in case this is ever lost: https://docs.google.com/spreadsheet/ccc?key=0Aujm_HldNh4WdHJ...
It’s hard to start a revolution by selling an app
Surviving as an entrepreneur. Why we need a Universal Basic Income.
Dawkins, rape culture, hurricanes and more- what the internet's discussed lately
Peer review for the Internet - rbutr
Rbutr is now available on Firefox
The Internet is Broken....
MyWOT Rating Exchanges now a thing?
An Open Letter to Neil deGrasse Tyson, Bill Nye and Adam Savage
Read Rebuttals, Get Kittens - Fact-Checking the Internet meets pop culture
But of course, everyone and anyone can add rebuttals, so please, feel free to add any whenever you happen across one :)
Is that what you meant?
For example, one link:http://rbutr.com/rbutr/WebsiteServlet?requestType=showLink&#... where the rebuttal is rebutted: http://rbutr.com/rbutr/WebsiteServlet?requestType=showLinksB... where the rebuttal is rebutted: http://rbutr.com/rbutr/WebsiteServlet?requestType=showLinksB...
As of yet though, we are unable to replicate the problems. If you could provide some details of your OS and browser, and exactly what happened, I would appreciate it.
Because normally, copy and pasting a URL in to the rebuttal place actually isn't allowed at all. So something has gone very wrong! Also, the Tag box is indeed normally editable (after addition of the first tag).
So I just wanted to let you know, that there is a bug causing those faults, and we haven't identified what is causing that bug yet...
However, in order to use these functions, there needs to be a user account for it. Otherwise people might 'test' things out and create nonsense links. Repeatedly. User accounts are a necessary filter in order to ensure we aren't inundated with testing clicks, and to provide quality control, and all the other things which follow from having registered users.
Most every page these days requires registration, so I don't think this is particularly odd.
Though we are now looking at creating a membership-free installation which allows you to complete our tutorial - and if we can, I would like it if that un-registered version could also deliver rebuttal alerts... So feedback is working. Now it will just take time to implement it all!
Definitely the chicken-egg problem is our main hurdle, but we are working on that by turning this project in to something more than just the plugin. We are also focusing on connecting with the most active communities who already engage in exactly the sort of activity which we need - the Skeptic community is exactly that community. So we are walking away from chickens and eggs, and going straight after the seeds.